Thomas aitken



I (No Model.)

T. AITKEN.

GOAL ANDR GK'DRILLING MACHINE. No. 289,595. z I Patented Dec. 4', 1883.

lll l' UNITED STATES,

PATENT OFFICE.

THOMAS AITKEN, OF.PITTSTON, PENNSYLVANIA.

COAL AND ROCK DRILLING MACHINE.

SPECIFICATION forming part of Letters Patent No. 289,595, dated December 4, 1883,

Application filed June 16, 1883. (No model.)

.To all whom it may concern:

Be it known that I, THOMAS AITKEN, of Pittston, in the county of Luzerne and State of Pennsylvania, have invented a new'and Improved Coal and Rock Drilling Machine, of which the following is a full, clear, and exact description.

My present invention relates to drilling-machines shown in the Letters Patent granted to me August 30, 1881, No. 246,440;

r and it consists in improved means for securing the bar or post which carries the swivel and drill-rod, as hereinafter described and claimed. Reference is to be had to the accompanying drawings, forming apart of this specification,

in which similar letters of reference indicate corresponding parts in all the figures.

Figure 1 is a side elevation of my improved drilling apparatus as set up for use. Fig. 2 is a side view of the lower portion of the post or bar. Fig. 3 is a side view at right angles to Fig. 2. I

A is the bar or post, carrying the swivel B and screw-rod O, as usual; The bar is formed square, and to its lower end a sharp-ended pawl, D, is .pivoted by a pin, a.

E is the wedge, attached to the bar A by means of links b, that are pivoted on both the wedge and the bar, and slotted, so that they may slide upon the pin to allow of the manipulation of the wedge. As shown in Fig. 2, the pawl, D is forked at its end which is attached' to the bar A, and the wedge E passes between the forks of the pawl.

In order to fix the post or bar A in position, ahole is drilled, as usual/ and the bar, with its pawl and wedge, inserted, as shown in Fig. 1, the wedge being then driven down to force the pawl D outward, so that the lower pointthe class of pawl, as described.

ed end of the latter is forced into the coal or rock at the bottom of the hole. At the same time, the wedge binding at the outer end of I the pawl, the bar A is thus held firmly and securely at these two points, instead of being held onlyat the outer portion of the hole, and a'space is left at the bottom to allow movement of the bar under heavy strain.

Fig. 3 shows the position of the wedge and the pawl D when the bar is clamped, and to give additional hold the bar may be shouldered or toothed upon the side opposite to the wedge. The wedge being fastened to the bar, it is always at hand, and not liable to .become separated therefrom.

The crank F of the screw-rod O is made with two or more holes to set upon the shouldered end of the rod, to reduceor increase the length of the crank, according to the power required. This construction saves the necessity of a set-screw, which is liable to be. lost or mislaid.

I am aware that a fastening device for a drill= frame has been formed of a swiveled head with slotted arm, a fixed and movable j aw, a cone, a crank-shaft, and spurs 011 the outside 'ofjaws; but

What I do claim as new and of my inven tion is The combination of the post A, pivoted forked pawl D near its end, the slotted link 1), working on a pin of post, and wedge E, pivoted to link and working between the forks of Witnesses:-

WM. ALLEN, PAT GIBBoNs.

THOMAS AITKEN. 

